In general, packing materials are used not only to enhance the appearance of packed goods, but also to protect the packed goods against external impacts. In particular, in packing of electrical and electronic products or automobile parts such as, bumpers, fenders, doors, and the like, a first foaming paper sheet or an air cap wrapping sheet is generally used to separate the electrical and electronic parts and the automobile parts from an inner surface of a box wall inside of a paper box such that an impact force which may be externally applied to packed goods is absorbed and alleviated.
In the case of the air cap wrapping sheet, there is a problem in that the volume of air caps is inevitably large due to the air caps sealed in units of cells, causing an excessive increase in logistics costs such as transportation costs.
Meanwhile, in an effort to solve such a problem of the air cap wrapping sheet in the related art, Patent Documents 1 to 3 and the like have been proposed.
Patent Document 1 (Korean Patent No. 10-1482311) relates to a packing bag with a cushioning function, which includes a first cushioning air column part composed of multiple air columns, a second cushioning air column part composed of multiple air columns and connected to the first cushioning air column part to form an accommodation space for accommodating goods, and a tie connected to the first cushioning air column part and/or connected to the second cushioning air column part to close an entrance of the accommodation space.
Furthermore, Patent Document 2 (Korean Patent No. 10-1351072) relates to a package equipped with a double air bag and a packaging method thereof, the package including an inner cushioning part composed of a pair of backing sheets coupled to each other, the inner cushioning part in which air is filled and forming an accommodating portion for accommodating a packaging object; an outer cushioning part surrounding the inner cushioning part and in which air is filled; and an air injection part to which air is injected through an air inlet, wherein the air injection part is configured to communicate with the inner and outer cushioning parts via both an air filling inlet of the inner cushioning part and an air filling inlet of the outer cushioning part, whereby air filling of the inner and outer cushioning parts is completed by only one air injection through the air injection part.
Patent Document 3 (Korean Patent No. 10-0995179) relates to a bendable multi-sectional cushioning cover bag including a packaging box, a first air tube, a second air tube, and a light-reflecting sheet. Herein, an end of the second air tube is connected to the first air tube and communicates therewith. Furthermore, multiple first cushioning parts provided at the first air tube and multiple second cushioning parts provided at the second air tube correspond to each other, and each of the second cushioning parts and each of the first cushioning parts corresponding thereto are adhered together by means of heat sealing at respective three sides thereof, thus forming an accommodation space in which goods are mounted.
The packing bag, the package, and the cover bag disclosed in Patent Documents 1 to 3 can be transported and stored and in a state of not injecting air and thus are significantly reduced in volume as compared with the air cap packing sheet in the related art, resulting in a significant reduction in logistics costs such as transportation costs. In addition, air can be injected before use to realize a cushioning function, thus safely packing goods. Meanwhile, a predetermined insulation property is provided by air cells into which air is injected. However, the air cells are welded together, which may cause a problem in that heat exchange is increased by welded portions, resulting in a significant reduction in insulation.